Boot for hot-air stacks



Patented .iuiy 22, 1930 unirse s rains JOHN J. HOLUB, OF GIGERO, ILLINOIS, ASSIGNOR TO THE EX CE-LSIOR STEEL FURNACE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS BOOT FOR HOT-AIR STACKS Application filed May 4,

My present invention relates to improvements in boots for hot air stacks. I-Iot air stacks are the conduits formed of rectangular sections which are installed betwcin the studding and joists of buildings to convey the air from the furnace to the divers portions of the building it is desired to heat. The con nection to the furnace is made with a round pipe and the boot to which my invention ap plies is the fitting assembling at the top w th the rectangular stack and at the bottom w th the round pipe from the furnace. The circular collar at the bottom of such boots gives the lower ends thereof considerable and sufficient stability but the rectangular upper ends of such boots have heretofore been of less sturdy and dependable construction by reason of their rectangular shape, the parallel walls of which are relatively easily pressed to gether or separated.

Heretofore, as far as I am aware, it'has been the practice to extend the walls of such boots vertically at a point where they reach the desired rectangular form and dimension to form the tongue which enters into and makes connection with the stack.

In my present construction I depart from the aforementioned general practice by bending the wall of the boot at the aforementioned point inwardly and then extending it vertically to form the entering tongue. Such a structure provides an abutment for the end of the stack and makes a much neater and more workmanlike job when the boot and stack are assembled. Further, by so insetting the tongue I am permitted to insert within the tongue a reinforcing rectangle of metal, the lower edges of which I bend outwardly to engage the inner faces of the walls of the boot, thereby making a much sturdier and more dependable structure. The reinforcing rectangle and tongue are secured together by enfolding the upper edge of the tongue over the reinforcing rectangle and diagonally crimping the upper edges of these arts.

lVhile this structure is stronger and neater than boots made in accordance with the former practice. it is less expensive to fabrirate.

1929. Serial No. 360,557;

I attain the foregoing objects and results by means of the structure illustrated in the accompanying drawing in which.

,Fig. 1 is a perspective of a boot embodying my present invention, i i

- Fig. 2 is a perspective ofthe reinforcing rectangle, and

Fig. 3 is a cross-sectional view on line 3 s of Fig. 1.

Similar reference characters refer to simii the circular to therectangular form has been completed I provide the inset head '7 from the top of which the metal is bent inwardly and downwardly, as at 8, and then upwardly to form the tongue 9, I have provided this tongue 9 with a small outwardly extending bead 10 for interlocking with the stack, but i this bead is not'a part of my present invention.

The reinforcing rectangle as shown in Fig. 2, consists of side walls 11-l1 and end walls 12-12 seamed together at their junctures. Th'e outer faces of the walls of the rectangular reinforcement fit against the inner face of the tongue 9. The lower edges of the ends and side walls are not beaded together but are bent outwardly to meet and abut the inner face of the walls of the boot.

After the reinforcing rectangle and tongue of the boot are assembled the upper edges of the tongue are bent within the reinforcing rectangle, as shown at 13 in Fig. 3, and the parts are provided with the oblique crimps 14 to hold these parts in assembly.

Having described my invention what I claim as new and desire to secure by Letters Patent is:

1. A boot for hot air stacks comprising a circular collar, and metal secured to said collar and arising therefrom developed to secure a rectangular section at the end opposite said collar, said walls at the point of {1'00 attaining a rectangle being inturned to form a supporting shoulder and then upturned to provide a tongue, a reinforcing rectangle fitting Within said tongue and having depending edges inclined outwardly to abut the inner faces of the Walls of said boot and means for securing said reinforcing rectangle Within said tongue.

2. A boot for hot air stacks comprising a circular collar, and metal secured to said collar and arising therefrom developed to secure a rectangular section at the end opposite said collar, said Walls at the point of attaining a rectangle being inturned to form a supporting shoulder and then upturned to provide a tongue. a reinforcing rectangle fitting with in said tongue and having depending edges inclined outwardly to abut the inner faces of the Walls of said boot, the upper edges of said tongue being folded over and Within and diagonally criniped upon said rectangle.

JOHN J. HOLUB. 

